Phthalic anhydride or phthalic acid anhydride is a toxic white solid crystal with low solubility in hot water and is one of the first bicarbonate dihydroxyacid acids. It is soluble in alcohol and carbon disulfide and reacts with strong oxides. For example, when heated with copper oxide or sodium nitrate, it reacts strongly and there is even a risk of it exploding.
How to produce phthalic anhydride?
In the laboratory, it is possible to produce this substance by using a suitable oxidant through the oxidation of naphthalene or ortho-xylene or by heating the phthalic acid and dissolving it in water and phthalic anhydride and sublimating it at the same temperature. Other methods of production that are mostly used in industry include oxidation of naphthalene with air oxygen in the vicinity of a suitable catalyst such as vanadium pentaxide or by oxidation of ortho-xylene and air oxygen in the vicinity of a catalyst.
Use of phthalic anhydride
It has many applications in various sectors of the industry, for example as a leader for a variety of reactants in organic compounds, in the production of plastic from vinyl chloride, for large-scale production of plastic lubricants, in the production of paints, pigments, resins. Polyester, alkyd resins, for the preparation of anhydroquinone kinisarine dye by reaction with paraclofenol and then hydrolysis of chloride, in solvent-based coatings for machinery, furniture and cosmetics, in the manufacture of detergents, herbicides and insecticides, Refractory materials, cross-linking agents of polysaccharide resins and polyester polyurethanes, are used in the production of drugs, food industries such as saccharin, methyl entraanalytes, and so on.
What are the risks and harms of phthalic anhydride?
Proximity or short-term exposure to this substance in humans includes irritation of the eyes, respiratory system and skin, but does not pose serious risks, but prolonged exposure to it can irritate the skin, damage lung cells and diseases such as conjunctivitis. Rhinitis, rhinoconjunctivitis, bronchitis, and mucous membranes of the respiratory tract.